It is quite discrete, but when you walk by the Bourse, you will see that actually the new Brussels was built on the old one. And I must say it is quite impressive! It's not like Edimburgh for those of you who know it, but still you wouldn't think that below the current Brussels there is a hidden city!
FYI Brussels was built on a swamp centuries ago and from there they have started constructing the city and there are still old parts of the underground city that can be seen from the surface! This shows you what was excavated a few years back! There are more places like this one that were discovered only a few years ago.
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